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1.
Int J Biol Macromol ; 255: 128089, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37979746

RESUMO

Oral medications are prone to gastric degradation and enzymatic inactivation, diminishing their efficacy. This study investigates a solution by developing intelligent polymeric networks, incorporating chitosan, methacrylic acid, N, N, methylene bisacrylamide, and montmorillonite clay, to enable the controlled release of Diloxanide Furoate (DF), an anti-protozoal drug. Employing a swelling-assisted diffusion technique, drug loading percentages varied from 63.96 % to 76.82 % among different formulations. Increased chitosan and methacrylic acid content enhanced drug loading, while N, N, methylene bisacrylamide and montmorillonite clay demonstrated an inverse relationship affecting diffusion and swelling. Equilibrium swelling studies unveiled formulation-dependent behaviors, with chitosan reducing swelling and methacrylic acid promoting it. Higher N, N, methylene bisacrylamide concentrations decreased swelling, indicating a denser cross-linked structure, while montmorillonite clay reduced hydrophilicity and swelling capacity. Further analyses confirmed successful gel formation, particularly in formulations with higher chitosan, methacrylic acid, and N, N, methylene bisacrylamide content, while montmorillonite clay limited gel fraction due to restricted polymer chain mobility. Techniques such as Fourier transform infrared spectroscopy, Differential scanning calorimetry, and thermal gravimetric analyses supported network development, enhancing thermal stability and cross-linking density. This research underscores the flexibility of polymeric networks for precise drug delivery, offering potential advancements in targeted therapies for various medical conditions.


Assuntos
Quitosana , Quitosana/química , Preparações de Ação Retardada , Bentonita/metabolismo , Argila , Polímeros/metabolismo , Colo/metabolismo
2.
Heliyon ; 9(10): e20852, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37916109

RESUMO

The analytical soliton solutions place a lot of value on birefringent fibres. The major goal of this study is to generate novel forms of soliton solutions for the Radhakrishnan-Kundu-Lakshmanan equation, which depicts unstable optical solitons that arise from optical propagations using birefringent fibres. The (presumably new) extended direct algebraic (EDA) technique is used here to extract a large number of solutions for RKLE. It gives soliton solutions up to thirty-seven, which essentially correspond to all soliton families. This method's ability to determine many sorts of solutions through a single process is one of its key advantages. Additionally, it is simple to infer that the technique employed in this study is really straightforward yet one of the quite effective approaches to solving nonlinear partial differential equations so, this novel extended direct algebraic (EDA) technique may be regarded as a comprehensive procedure. The resulting solutions are found to be hyperbolic, periodic, trigonometric, bright and dark, combined bright-dark, and W-shaped soliton, and these solutions are visually represented by means of 2D, 3D, and density plots. The present study can be extended to investigate several other nonlinear systems to understand the physical insights of the optical propagations through birefringent fibre.

3.
Adv Microb Physiol ; 83: 221-307, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37507160

RESUMO

Gram-negative bacteria are uniquely equipped to defeat antibiotics. Their outermost layer, the cell envelope, is a natural permeability barrier that contains an array of resistance proteins capable of neutralizing most existing antimicrobials. As a result, its presence creates a major obstacle for the treatment of resistant infections and for the development of new antibiotics. Despite this seemingly impenetrable armor, in-depth understanding of the cell envelope, including structural, functional and systems biology insights, has promoted efforts to target it that can ultimately lead to the generation of new antibacterial therapies. In this article, we broadly overview the biology of the cell envelope and highlight attempts and successes in generating inhibitors that impair its function or biogenesis. We argue that the very structure that has hampered antibiotic discovery for decades has untapped potential for the design of novel next-generation therapeutics against bacterial pathogens.


Assuntos
Antibacterianos , Bactérias Gram-Negativas , Antibacterianos/química , Membrana Celular/metabolismo , Bactérias Gram-Negativas/metabolismo , Parede Celular/metabolismo
4.
Br J Haematol ; 202(2): 289-293, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37194132

RESUMO

Systemic AL amyloidosis is an incurable condition with various presentations and may cause multiple complications related to organ involvement. As survival has improved, disease and therapy-related quality of life (QoL) is becoming an increasingly important treatment endpoint. We review the literature summarising the utilised QoL questionnaires (QLQs) and assess their validity according to COSMIN (Consensus-based Standards for the Selection of Health Measurement Instruments) standards. Thirteen retrospective observational studies and thirty-two prospective clinical trials were analysed. Most QLQs are generic or only validated in populations with distinct complications of the disease. None meet 'strong evidence' for validation in this context. There is a need to develop a disease-specific QLQ, which could inform treatment choices and facilitate the approval of novel therapies.


Assuntos
Amiloidose de Cadeia Leve de Imunoglobulina , Qualidade de Vida , Humanos , Amiloidose de Cadeia Leve de Imunoglobulina/terapia , Estudos Prospectivos , Estudos Retrospectivos , Medidas de Resultados Relatados pelo Paciente , Inquéritos e Questionários
5.
Polymers (Basel) ; 15(2)2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36679191

RESUMO

This research was carried out to create a pH-responsive polymeric system for the targeted drug delivery of Diloxanide furoate. It relied on sodium alginate (Na-Alg) and Carbopol 934P as building blocks. Using an aqueous free radical polymerization method, SCH1-SCH12 was created with varying polymer, MAA, and MBA input ratios. Positive outcomes were seen in the swelling and release profiles at higher pH levels. Hydrogel formation, as well as component compatibility, thermal stability, and Diloxanide furoate loading, were all validated by instrumental characterization. A drug loading percentage of 83.56% was determined, with the swelling reaching 743.19%. For the formulation with MBA, the gel fraction was 94.58%. The release of diloxanide furoate increased to 91.77% at neutral pH. The formulation containing Carbopol 934P provided the highest mucoadhesion force (3993.42 dynes/cm2). The created hydrogel has been shown to be biocompatible by toxicological testing of the network. Based on the findings, the created polymeric nexus proved promising for pH-dependent localized and regulated delivery of Diloxanide furoate.

6.
J Food Biochem ; 44(8): e13320, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32542898

RESUMO

Herein, the methanolic extract of Rumex hastatus was prepared and subjected to silica gel column chromatographic separation for purification. The chromatographic analysis yielded four bioactive compounds namely, 1,8-dihydroxy-3-methyl-anthraquinone (C1, chrysophanol), 3-methoxy-7-methyl-1,5-dihydroxy-anthraquinone (C2), 6-methyl-1,3,7-trihydroxy-anthraquinone (C3), and 4-hydroxycinnamic acid (C4). The structures of all the isolated bio-entities were elucidated by spectroscopic analysis (1D, 2D-NMR, and MS). The biological potentialities of bioactive compounds were evaluated by determining their antioxidant and anti-urease activities. The results revealed that compound 1 showed the highest nitrite radical scavenging activity (IC50  = 0.39 mM) followed by C2 and C4 (IC50  = 0.45) mM and C3 (IC50  = 0.47 mM). Similarly, the determined IC50  values for anti-urease activity were C2 (IC50  = 0.39 mM), C1 (IC50  = 0.40), C4 (IC50  = 0.41), and C3 (IC50  = 44). Molecular docking study revealed maximum interactions among the hydroxyl group of all compounds. In conclusion, Rumex hastatus extract could be a promising alternative to chemical additives in pharmaceutical industries due to its noteworthy biological activities. PRACTICAL APPLICATIONS: As we have shown in this study that Rumex hastatus is a prolific source of biologically active compounds with potent antioxidant and anti-urease activities, therefore, R. hastatus extract could be used as a promising alternative to chemical additives in pharmaceutical industries due to its unique compounds and noteworthy biological activities.


Assuntos
Rumex , Antioxidantes/farmacologia , Simulação de Acoplamento Molecular , Extratos Vegetais/farmacologia , Urease
8.
J Immunotoxicol ; 9(1): 34-42, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22074378

RESUMO

Human peripheral blood mononuclear cells (PBMC) are routinely used in vitro to detect cytokine secretion as part of preclinical screens to delineate agonistic and antagonistic action of therapeutic monoclonal antibodies (mAbs). Preclinical value of standard human PBMC assays to detect cytokine release syndrome (CRS) has been questioned, as they did not predict the "cytokine storm" that occurred when healthy human volunteers were given a CD28-specific super-agonist mAb, TGN1412. In this article, we describe a three-dimensional biomimetic vascular test-bed that can be used as a more physiologically relevant assay for testing therapeutic Abs. For developing such a system, we used TGN1412 as a model mAb. We tested soluble TGN1412 on various combinations of human blood components in a module containing endothelial cells grown on a collagen scaffold and measured cytokine release using multiplex array. Our system, consisting of whole leukocytes, endothelial cells, and 100% autologous platelet-poor plasma (PPP) consistently produced proinflammatory cytokines in response to soluble TGN1412. In addition, other mAb therapeutics known to induce CRS or first infusion reactions, such as OKT3, Campath-1H, or Herceptin, generated cytokine profiles in our model system consistent with their in vivo responses. As a negative control we tested the non-CRS mAbs Avastin and Remicade and found little difference between these mAbs and the placebo control. Our data indicate that this novel assay may have preclinical value for predicting the potential of CRS for mAb therapeutics.


Assuntos
Anticorpos Monoclonais Humanizados/toxicidade , Biomimética , Citocinas/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Granulócitos/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Leucócitos Mononucleares/efeitos dos fármacos , Testes de Toxicidade , Células Cultivadas , Técnicas de Cocultura , Colágeno , Granulócitos/imunologia , Granulócitos/metabolismo , Células Endoteliais da Veia Umbilical Humana/imunologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Plasma , Medição de Risco , Fatores de Tempo , Alicerces Teciduais
9.
Stud Health Technol Inform ; 132: 426-32, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18391335

RESUMO

This paper reports on the computational simulation and modeling of an in vitro alveolar construct system along the optical coherence microscopy (OCM) methods for visualizing engineered tissue. The optical imaging methods will be compared to immunohistochemical light microscopy samples of engineered alveolar constructs. Results show depth images of the alveolar tissue construct for a bilayer construct, as well as predictions of the gas exchange process in a simple model of a bio-reactor hosting the construct.


Assuntos
Simulação por Computador , Comportamento Cooperativo , Imageamento Tridimensional/métodos , Troca Gasosa Pulmonar , Engenharia Tecidual , Humanos , Microscopia , Tomografia de Coerência Óptica , Estados Unidos
10.
In Vitro Cell Dev Biol Anim ; 43(2): 72-86, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17570021

RESUMO

Two porcine cell lines of yolk-sac visceral endoderm, designated as PE-1 and PE-2, were derived from in vivo 11-d porcine blastocysts that were either ovoid (PE-1) or at the early tubular stage of elongation (PE-2). Primary and secondary culture of the cell lines was done on STO feeder cells. The PE-1 and PE-2 cells morphologically resembled visceral endoderm previously cultured from in vivo-derived ovine and equine blastocysts and from in vitro-derived bovine blastocysts. Analysis of the PE-1- and PE-2-conditioned medium by 2D-gel electrophoresis and matrix-assisted laser desorption/ionization-time-of-flight-mass spectrometry demonstrated that they produced serum proteins. Reverse transcriptase polymerase chain reaction analysis showed that the cells expressed several genes typical for yolk-sac endoderm differentiation and function including GATA-6, DAB-2, REX-1, HNF-1, transthyretin, alpha-fetoprotein, and albumin. Unlike a porcine liver cell line, the PE-1 and PE-2 cell lines had relatively low inducible P-450 content and EROD activity, and, while they cleared ammonia from the cell culture medium, they did not produce urea. Transmission electron microscopy revealed that the cells were a polarized epithelium connected by complex junctions resembling tight junctions and by lateral desmosomes. Rough endoplasmic reticulum was prominent within the cells. Immunocytochemistry indicated that the PE-1 cells expressed cytokeratin 18 and had robust microtubule networks similar to those observed in in vivo porcine yolk-sac endoderm. Metaphase spreads prepared at passage 26 of the PE-1 cell line indicated a diploid porcine karyotype of 38 chromosomes. The cells have been grown for over 1 yr for multiple passages at 1:10 or 1:20 split ratios on STO feeder cells. The cell lines will be of interest as an in vitro model of the porcine preimplantation yolk-sac tissue.


Assuntos
Blastocisto/citologia , Linhagem Celular , Endoderma/citologia , Endoderma/metabolismo , Animais , Blastocisto/metabolismo , Blastocisto/ultraestrutura , Proteínas Sanguíneas/biossíntese , Forma Celular , Meios de Cultivo Condicionados , Proteínas do Citoesqueleto/biossíntese , Endoderma/ultraestrutura , Feminino , Expressão Gênica , Imuno-Histoquímica , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Suínos , Saco Vitelino
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